From 06f502f57d0d7728f9fa0f157ec5e4111ddb98f6 Mon Sep 17 00:00:00 2001 From: Ben Whitten Date: Sun, 10 Dec 2017 21:17:55 +0000 Subject: [PATCH] leds: trigger: Introduce a NETDEV trigger This commit introduces a NETDEV trigger for named device activity. Available triggers are link, rx, and tx. Signed-off-by: Ben Whitten Acked-by: Pavel Machek Signed-off-by: Jacek Anaszewski --- .../ABI/testing/sysfs-class-led-trigger-netdev | 45 ++ drivers/leds/trigger/Kconfig | 7 + drivers/leds/trigger/Makefile | 1 + drivers/leds/trigger/ledtrig-netdev.c | 496 +++++++++++++++++++++ 4 files changed, 549 insertions(+) create mode 100644 Documentation/ABI/testing/sysfs-class-led-trigger-netdev create mode 100644 drivers/leds/trigger/ledtrig-netdev.c --- /dev/null +++ b/Documentation/ABI/testing/sysfs-class-led-trigger-netdev @@ -0,0 +1,45 @@ +What: /sys/class/leds//device_name +Date: Dec 2017 +KernelVersion: 4.16 +Contact: linux-leds@vger.kernel.org +Description: + Specifies the network device name to monitor. + +What: /sys/class/leds//interval +Date: Dec 2017 +KernelVersion: 4.16 +Contact: linux-leds@vger.kernel.org +Description: + Specifies the duration of the LED blink in milliseconds. + Defaults to 50 ms. + +What: /sys/class/leds//link +Date: Dec 2017 +KernelVersion: 4.16 +Contact: linux-leds@vger.kernel.org +Description: + Signal the link state of the named network device. + If set to 0 (default), the LED's normal state is off. + If set to 1, the LED's normal state reflects the link state + of the named network device. + Setting this value also immediately changes the LED state. + +What: /sys/class/leds//tx +Date: Dec 2017 +KernelVersion: 4.16 +Contact: linux-leds@vger.kernel.org +Description: + Signal transmission of data on the named network device. + If set to 0 (default), the LED will not blink on transmission. + If set to 1, the LED will blink for the milliseconds specified + in interval to signal transmission. + +What: /sys/class/leds//rx +Date: Dec 2017 +KernelVersion: 4.16 +Contact: linux-leds@vger.kernel.org +Description: + Signal reception of data on the named network device. + If set to 0 (default), the LED will not blink on reception. + If set to 1, the LED will blink for the milliseconds specified + in interval to signal reception. --- a/drivers/leds/trigger/Kconfig +++ b/drivers/leds/trigger/Kconfig @@ -126,4 +126,11 @@ config LEDS_TRIGGER_PANIC a different trigger. If unsure, say Y. +config LEDS_TRIGGER_NETDEV + tristate "LED Netdev Trigger" + depends on NET && LEDS_TRIGGERS + help + This allows LEDs to be controlled by network device activity. + If unsure, say Y. + endif # LEDS_TRIGGERS --- a/drivers/leds/trigger/Makefile +++ b/drivers/leds/trigger/Makefile @@ -10,3 +10,4 @@ obj-$(CONFIG_LEDS_TRIGGER_DEFAULT_ON) += obj-$(CONFIG_LEDS_TRIGGER_TRANSIENT) += ledtrig-transient.o obj-$(CONFIG_LEDS_TRIGGER_CAMERA) += ledtrig-camera.o obj-$(CONFIG_LEDS_TRIGGER_PANIC) += ledtrig-panic.o +obj-$(CONFIG_LEDS_TRIGGER_NETDEV) += ledtrig-netdev.o --- /dev/null +++ b/drivers/leds/trigger/ledtrig-netdev.c @@ -0,0 +1,496 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright 2017 Ben Whitten +// Copyright 2007 Oliver Jowett +// +// LED Kernel Netdev Trigger +// +// Toggles the LED to reflect the link and traffic state of a named net device +// +// Derived from ledtrig-timer.c which is: +// Copyright 2005-2006 Openedhand Ltd. +// Author: Richard Purdie + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include "../leds.h" + +/* + * Configurable sysfs attributes: + * + * device_name - network device name to monitor + * interval - duration of LED blink, in milliseconds + * link - LED's normal state reflects whether the link is up + * (has carrier) or not + * tx - LED blinks on transmitted data + * rx - LED blinks on receive data + * + */ + +struct led_netdev_data { + spinlock_t lock; + + struct delayed_work work; + struct notifier_block notifier; + + struct led_classdev *led_cdev; + struct net_device *net_dev; + + char device_name[IFNAMSIZ]; + atomic_t interval; + unsigned int last_activity; + + unsigned long mode; +#define NETDEV_LED_LINK 0 +#define NETDEV_LED_TX 1 +#define NETDEV_LED_RX 2 +#define NETDEV_LED_MODE_LINKUP 3 +}; + +enum netdev_led_attr { + NETDEV_ATTR_LINK, + NETDEV_ATTR_TX, + NETDEV_ATTR_RX +}; + +static void set_baseline_state(struct led_netdev_data *trigger_data) +{ + int current_brightness; + struct led_classdev *led_cdev = trigger_data->led_cdev; + + current_brightness = led_cdev->brightness; + if (current_brightness) + led_cdev->blink_brightness = current_brightness; + if (!led_cdev->blink_brightness) + led_cdev->blink_brightness = led_cdev->max_brightness; + + if (!test_bit(NETDEV_LED_MODE_LINKUP, &trigger_data->mode)) + led_set_brightness(led_cdev, LED_OFF); + else { + if (test_bit(NETDEV_LED_LINK, &trigger_data->mode)) + led_set_brightness(led_cdev, + led_cdev->blink_brightness); + else + led_set_brightness(led_cdev, LED_OFF); + + /* If we are looking for RX/TX start periodically + * checking stats + */ + if (test_bit(NETDEV_LED_TX, &trigger_data->mode) || + test_bit(NETDEV_LED_RX, &trigger_data->mode)) + schedule_delayed_work(&trigger_data->work, 0); + } +} + +static ssize_t device_name_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct led_classdev *led_cdev = dev_get_drvdata(dev); + struct led_netdev_data *trigger_data = led_cdev->trigger_data; + ssize_t len; + + spin_lock_bh(&trigger_data->lock); + len = sprintf(buf, "%s\n", trigger_data->device_name); + spin_unlock_bh(&trigger_data->lock); + + return len; +} + +static ssize_t device_name_store(struct device *dev, + struct device_attribute *attr, const char *buf, + size_t size) +{ + struct led_classdev *led_cdev = dev_get_drvdata(dev); + struct led_netdev_data *trigger_data = led_cdev->trigger_data; + + if (size >= IFNAMSIZ) + return -EINVAL; + + cancel_delayed_work_sync(&trigger_data->work); + + spin_lock_bh(&trigger_data->lock); + + if (trigger_data->net_dev) { + dev_put(trigger_data->net_dev); + trigger_data->net_dev = NULL; + } + + strncpy(trigger_data->device_name, buf, size); + if (size > 0 && trigger_data->device_name[size - 1] == '\n') + trigger_data->device_name[size - 1] = 0; + + if (trigger_data->device_name[0] != 0) + trigger_data->net_dev = + dev_get_by_name(&init_net, trigger_data->device_name); + + clear_bit(NETDEV_LED_MODE_LINKUP, &trigger_data->mode); + if (trigger_data->net_dev != NULL) + if (netif_carrier_ok(trigger_data->net_dev)) + set_bit(NETDEV_LED_MODE_LINKUP, &trigger_data->mode); + + trigger_data->last_activity = 0; + + set_baseline_state(trigger_data); + spin_unlock_bh(&trigger_data->lock); + + return size; +} + +static DEVICE_ATTR_RW(device_name); + +static ssize_t netdev_led_attr_show(struct device *dev, char *buf, + enum netdev_led_attr attr) +{ + struct led_classdev *led_cdev = dev_get_drvdata(dev); + struct led_netdev_data *trigger_data = led_cdev->trigger_data; + int bit; + + switch (attr) { + case NETDEV_ATTR_LINK: + bit = NETDEV_LED_LINK; + break; + case NETDEV_ATTR_TX: + bit = NETDEV_LED_TX; + break; + case NETDEV_ATTR_RX: + bit = NETDEV_LED_RX; + break; + default: + return -EINVAL; + } + + return sprintf(buf, "%u\n", test_bit(bit, &trigger_data->mode)); +} + +static ssize_t netdev_led_attr_store(struct device *dev, const char *buf, + size_t size, enum netdev_led_attr attr) +{ + struct led_classdev *led_cdev = dev_get_drvdata(dev); + struct led_netdev_data *trigger_data = led_cdev->trigger_data; + unsigned long state; + int ret; + int bit; + + ret = kstrtoul(buf, 0, &state); + if (ret) + return ret; + + switch (attr) { + case NETDEV_ATTR_LINK: + bit = NETDEV_LED_LINK; + break; + case NETDEV_ATTR_TX: + bit = NETDEV_LED_TX; + break; + case NETDEV_ATTR_RX: + bit = NETDEV_LED_RX; + break; + default: + return -EINVAL; + } + + cancel_delayed_work_sync(&trigger_data->work); + + if (state) + set_bit(bit, &trigger_data->mode); + else + clear_bit(bit, &trigger_data->mode); + + set_baseline_state(trigger_data); + + return size; +} + +static ssize_t link_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + return netdev_led_attr_show(dev, buf, NETDEV_ATTR_LINK); +} + +static ssize_t link_store(struct device *dev, + struct device_attribute *attr, const char *buf, size_t size) +{ + return netdev_led_attr_store(dev, buf, size, NETDEV_ATTR_LINK); +} + +static DEVICE_ATTR_RW(link); + +static ssize_t tx_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + return netdev_led_attr_show(dev, buf, NETDEV_ATTR_TX); +} + +static ssize_t tx_store(struct device *dev, + struct device_attribute *attr, const char *buf, size_t size) +{ + return netdev_led_attr_store(dev, buf, size, NETDEV_ATTR_TX); +} + +static DEVICE_ATTR_RW(tx); + +static ssize_t rx_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + return netdev_led_attr_show(dev, buf, NETDEV_ATTR_RX); +} + +static ssize_t rx_store(struct device *dev, + struct device_attribute *attr, const char *buf, size_t size) +{ + return netdev_led_attr_store(dev, buf, size, NETDEV_ATTR_RX); +} + +static DEVICE_ATTR_RW(rx); + +static ssize_t interval_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct led_classdev *led_cdev = dev_get_drvdata(dev); + struct led_netdev_data *trigger_data = led_cdev->trigger_data; + + return sprintf(buf, "%u\n", + jiffies_to_msecs(atomic_read(&trigger_data->interval))); +} + +static ssize_t interval_store(struct device *dev, + struct device_attribute *attr, const char *buf, + size_t size) +{ + struct led_classdev *led_cdev = dev_get_drvdata(dev); + struct led_netdev_data *trigger_data = led_cdev->trigger_data; + unsigned long value; + int ret; + + ret = kstrtoul(buf, 0, &value); + if (ret) + return ret; + + /* impose some basic bounds on the timer interval */ + if (value >= 5 && value <= 10000) { + cancel_delayed_work_sync(&trigger_data->work); + + atomic_set(&trigger_data->interval, msecs_to_jiffies(value)); + set_baseline_state(trigger_data); /* resets timer */ + } + + return size; +} + +static DEVICE_ATTR_RW(interval); + +static int netdev_trig_notify(struct notifier_block *nb, + unsigned long evt, void *dv) +{ + struct net_device *dev = + netdev_notifier_info_to_dev((struct netdev_notifier_info *)dv); + struct led_netdev_data *trigger_data = container_of(nb, + struct + led_netdev_data, + notifier); + + if (evt != NETDEV_UP && evt != NETDEV_DOWN && evt != NETDEV_CHANGE + && evt != NETDEV_REGISTER && evt != NETDEV_UNREGISTER + && evt != NETDEV_CHANGENAME) + return NOTIFY_DONE; + + if (strcmp(dev->name, trigger_data->device_name)) + return NOTIFY_DONE; + + cancel_delayed_work_sync(&trigger_data->work); + + spin_lock_bh(&trigger_data->lock); + + clear_bit(NETDEV_LED_MODE_LINKUP, &trigger_data->mode); + switch (evt) { + case NETDEV_REGISTER: + if (trigger_data->net_dev) + dev_put(trigger_data->net_dev); + dev_hold(dev); + trigger_data->net_dev = dev; + break; + case NETDEV_CHANGENAME: + case NETDEV_UNREGISTER: + if (trigger_data->net_dev) { + dev_put(trigger_data->net_dev); + trigger_data->net_dev = NULL; + } + break; + case NETDEV_UP: + case NETDEV_CHANGE: + if (netif_carrier_ok(dev)) + set_bit(NETDEV_LED_MODE_LINKUP, &trigger_data->mode); + break; + } + + set_baseline_state(trigger_data); + + spin_unlock_bh(&trigger_data->lock); + + return NOTIFY_DONE; +} + +/* here's the real work! */ +static void netdev_trig_work(struct work_struct *work) +{ + struct led_netdev_data *trigger_data = container_of(work, + struct + led_netdev_data, + work.work); + struct rtnl_link_stats64 *dev_stats; + unsigned int new_activity; + struct rtnl_link_stats64 temp; + unsigned long interval; + int invert; + + /* If we dont have a device, insure we are off */ + if (!trigger_data->net_dev) { + led_set_brightness(trigger_data->led_cdev, LED_OFF); + return; + } + + /* If we are not looking for RX/TX then return */ + if (!test_bit(NETDEV_LED_TX, &trigger_data->mode) && + !test_bit(NETDEV_LED_RX, &trigger_data->mode)) + return; + + dev_stats = dev_get_stats(trigger_data->net_dev, &temp); + new_activity = + (test_bit(NETDEV_LED_TX, &trigger_data->mode) ? + dev_stats->tx_packets : 0) + + (test_bit(NETDEV_LED_RX, &trigger_data->mode) ? + dev_stats->rx_packets : 0); + + if (trigger_data->last_activity != new_activity) { + led_stop_software_blink(trigger_data->led_cdev); + + invert = test_bit(NETDEV_LED_LINK, &trigger_data->mode); + interval = jiffies_to_msecs( + atomic_read(&trigger_data->interval)); + /* base state is ON (link present) */ + led_blink_set_oneshot(trigger_data->led_cdev, + &interval, + &interval, + invert); + trigger_data->last_activity = new_activity; + } + + schedule_delayed_work(&trigger_data->work, + (atomic_read(&trigger_data->interval)*2)); +} + +static void netdev_trig_activate(struct led_classdev *led_cdev) +{ + struct led_netdev_data *trigger_data; + int rc; + + trigger_data = kzalloc(sizeof(struct led_netdev_data), GFP_KERNEL); + if (!trigger_data) + return; + + spin_lock_init(&trigger_data->lock); + + trigger_data->notifier.notifier_call = netdev_trig_notify; + trigger_data->notifier.priority = 10; + + INIT_DELAYED_WORK(&trigger_data->work, netdev_trig_work); + + trigger_data->led_cdev = led_cdev; + trigger_data->net_dev = NULL; + trigger_data->device_name[0] = 0; + + trigger_data->mode = 0; + atomic_set(&trigger_data->interval, msecs_to_jiffies(50)); + trigger_data->last_activity = 0; + + led_cdev->trigger_data = trigger_data; + + rc = device_create_file(led_cdev->dev, &dev_attr_device_name); + if (rc) + goto err_out; + rc = device_create_file(led_cdev->dev, &dev_attr_link); + if (rc) + goto err_out_device_name; + rc = device_create_file(led_cdev->dev, &dev_attr_rx); + if (rc) + goto err_out_link; + rc = device_create_file(led_cdev->dev, &dev_attr_tx); + if (rc) + goto err_out_rx; + rc = device_create_file(led_cdev->dev, &dev_attr_interval); + if (rc) + goto err_out_tx; + rc = register_netdevice_notifier(&trigger_data->notifier); + if (rc) + goto err_out_interval; + return; + +err_out_interval: + device_remove_file(led_cdev->dev, &dev_attr_interval); +err_out_tx: + device_remove_file(led_cdev->dev, &dev_attr_tx); +err_out_rx: + device_remove_file(led_cdev->dev, &dev_attr_rx); +err_out_link: + device_remove_file(led_cdev->dev, &dev_attr_link); +err_out_device_name: + device_remove_file(led_cdev->dev, &dev_attr_device_name); +err_out: + led_cdev->trigger_data = NULL; + kfree(trigger_data); +} + +static void netdev_trig_deactivate(struct led_classdev *led_cdev) +{ + struct led_netdev_data *trigger_data = led_cdev->trigger_data; + + if (trigger_data) { + unregister_netdevice_notifier(&trigger_data->notifier); + + device_remove_file(led_cdev->dev, &dev_attr_device_name); + device_remove_file(led_cdev->dev, &dev_attr_link); + device_remove_file(led_cdev->dev, &dev_attr_rx); + device_remove_file(led_cdev->dev, &dev_attr_tx); + device_remove_file(led_cdev->dev, &dev_attr_interval); + + cancel_delayed_work_sync(&trigger_data->work); + + if (trigger_data->net_dev) + dev_put(trigger_data->net_dev); + + kfree(trigger_data); + } +} + +static struct led_trigger netdev_led_trigger = { + .name = "netdev", + .activate = netdev_trig_activate, + .deactivate = netdev_trig_deactivate, +}; + +static int __init netdev_trig_init(void) +{ + return led_trigger_register(&netdev_led_trigger); +} + +static void __exit netdev_trig_exit(void) +{ + led_trigger_unregister(&netdev_led_trigger); +} + +module_init(netdev_trig_init); +module_exit(netdev_trig_exit); + +MODULE_AUTHOR("Ben Whitten "); +MODULE_AUTHOR("Oliver Jowett "); +MODULE_DESCRIPTION("Netdev LED trigger"); +MODULE_LICENSE("GPL v2");